Among the hundreds of people at the school were former and current students, like Omori, a skinny sixth grader with a passion for volleyball.

She looked bemused at the transformation of her school, its gym now hosting neat rows of blue mats for displaced people to sleep on.

Japanese students change into indoor shoes when they enter their school buildings, but her designated shoe box was now stuffed with rolled-up clothing, intended for some of the hundreds of evacuees staying at the school.

Around noon, clutching her mobile tablet, she joined her friends in line for a bowl of cold noodles and two rice balls for lunch.

Classes cancelled

Despite the unusual circumstances, the school remained quiet and orderly, with its new residents removing their shoes before entering their temporary home.

Families got together to designate people to stay at the school and look after their children so the adults could get back to their flood-damaged homes and begin the clean-up work.

In the school yard, dozens of vehicles were parked, and aid workers streamed in continuously carrying donations.